Dan Dawson
@meteodan.bsky.social
Associate Professor of Meteorology at Purdue University. Husband, father, and storm chaser. Nondenominational Christian. Insufferable centrist. I would like to keep my Republic. Opinions my own.
Reposted by Dan Dawson
@hebrooks87.bsky.social with a stirring tribute to the late Chuck Doswell at #ECSS. Chuck’s legacy lives on in his lasting ingredients-based flash flooding teachings.
November 19, 2025 at 11:16 AM
@hebrooks87.bsky.social with a stirring tribute to the late Chuck Doswell at #ECSS. Chuck’s legacy lives on in his lasting ingredients-based flash flooding teachings.
Just when I was about to go back inside! Aurora all quads!
November 12, 2025 at 4:57 AM
Just when I was about to go back inside! Aurora all quads!
"The wind in the wires made a tattle-tale sound, and a wave broke over the railing..."
To the hour and near minute.
"We are holding our own."
"We are holding our own."
November 11, 2025 at 2:26 AM
"The wind in the wires made a tattle-tale sound, and a wave broke over the railing..."
Reposted by Dan Dawson
You scrolled too greedily and too deep.
November 10, 2025 at 6:50 PM
You scrolled too greedily and too deep.
If anyone wonders how my evening is going, here’s a text I just sent to my Mom, divorced of all context for comedic and dramatic effect:
“The fact that Guy Smiley has no teeth in the Google search makes me wonder if the Mandela effect really is true :P”
“The fact that Guy Smiley has no teeth in the Google search makes me wonder if the Mandela effect really is true :P”
November 3, 2025 at 12:47 AM
If anyone wonders how my evening is going, here’s a text I just sent to my Mom, divorced of all context for comedic and dramatic effect:
“The fact that Guy Smiley has no teeth in the Google search makes me wonder if the Mandela effect really is true :P”
“The fact that Guy Smiley has no teeth in the Google search makes me wonder if the Mandela effect really is true :P”
Reposted by Dan Dawson
Thanks to some vigilant friends out there, I have a nearly-complete 87-hour radar loop of #Melissa 's approach to #Jamaica. The loop abruptly ends when the radar is lost (either loss of communication with it or loss of the actual structure).
bmcnoldy.earth.miami.edu/tropics/radar/
bmcnoldy.earth.miami.edu/tropics/radar/
October 29, 2025 at 12:03 PM
Thanks to some vigilant friends out there, I have a nearly-complete 87-hour radar loop of #Melissa 's approach to #Jamaica. The loop abruptly ends when the radar is lost (either loss of communication with it or loss of the actual structure).
bmcnoldy.earth.miami.edu/tropics/radar/
bmcnoldy.earth.miami.edu/tropics/radar/
Reposted by Dan Dawson
Echoing colleagues: Think before you (re)post. #Melissa is about to impact a relatively poor part of Jamaica. I doubt we will know the true extent of the devastation for days or weeks.
Information vacuums fill with disinformation. Expect a lot of “breaking wind” on SM.
Map source: World Bank
Information vacuums fill with disinformation. Expect a lot of “breaking wind” on SM.
Map source: World Bank
October 28, 2025 at 3:12 PM
Echoing colleagues: Think before you (re)post. #Melissa is about to impact a relatively poor part of Jamaica. I doubt we will know the true extent of the devastation for days or weeks.
Information vacuums fill with disinformation. Expect a lot of “breaking wind” on SM.
Map source: World Bank
Information vacuums fill with disinformation. Expect a lot of “breaking wind” on SM.
Map source: World Bank
Reposted by Dan Dawson
Meteorologist Matthew Cappucci flew into the eye of Hurricane Melissa, a Category 5 storm that is projected to hit Jamaica.
“It was equal parts scientifically stunning and horrifying from a humanitarian standpoint,” he wrote, flying in one of two groups of hurricane hunters. https://wapo.st/42XpWmq
“It was equal parts scientifically stunning and horrifying from a humanitarian standpoint,” he wrote, flying in one of two groups of hurricane hunters. https://wapo.st/42XpWmq
October 28, 2025 at 3:15 PM
Meteorologist Matthew Cappucci flew into the eye of Hurricane Melissa, a Category 5 storm that is projected to hit Jamaica.
“It was equal parts scientifically stunning and horrifying from a humanitarian standpoint,” he wrote, flying in one of two groups of hurricane hunters. https://wapo.st/42XpWmq
“It was equal parts scientifically stunning and horrifying from a humanitarian standpoint,” he wrote, flying in one of two groups of hurricane hunters. https://wapo.st/42XpWmq
A surface wind of 198 mph!
October 28, 2025 at 2:55 PM
A surface wind of 198 mph!
Reposted by Dan Dawson
With a pressure of 892 mb, Melissa is tied for the 3rd most intense Atlantic basin hurricane on record (by pressure) and if it holds at 185 mph through landfall in Jamaica, it would tie Dorian in 2019 as the strongest landfalling Atlantic basin hurricane on record.
October 28, 2025 at 2:32 PM
With a pressure of 892 mb, Melissa is tied for the 3rd most intense Atlantic basin hurricane on record (by pressure) and if it holds at 185 mph through landfall in Jamaica, it would tie Dorian in 2019 as the strongest landfalling Atlantic basin hurricane on record.
And of course BlueSky decided to only show the first frame of the PNG animation (even though it showed it animating just fine in the post preview). So here's another try at it using a GIF:
October 27, 2025 at 6:27 PM
And of course BlueSky decided to only show the first frame of the PNG animation (even though it showed it animating just fine in the post preview). So here's another try at it using a GIF:
I love how the high-frequency satellite imagery from GOES-19 (every minute) shows how the low-level circulation *within* the eye of #Melissa approaches that of a solid body. Notice how the pattern of clouds in the eye doesn't warp but rotates as if it were artwork on a spinning record. (1/3)
October 27, 2025 at 6:12 PM
I love how the high-frequency satellite imagery from GOES-19 (every minute) shows how the low-level circulation *within* the eye of #Melissa approaches that of a solid body. Notice how the pattern of clouds in the eye doesn't warp but rotates as if it were artwork on a spinning record. (1/3)
Reposted by Dan Dawson
“Step 1. A tropical disturbance is created when Mneseus, son of Poseidon and reigning King of Atlantis, strikes a deadly blow to a multi-headed hydra by ramming his trident through its heart“
theonion.com/how-hurrican...
theonion.com/how-hurrican...
How Hurricanes Form
In the midst of a record hurricane season, meteorologists are paying close attention as storms take shape and gather strength. Here’s a step-by-step guide to how hurricanes form.
theonion.com
October 27, 2025 at 4:51 PM
“Step 1. A tropical disturbance is created when Mneseus, son of Poseidon and reigning King of Atlantis, strikes a deadly blow to a multi-headed hydra by ramming his trident through its heart“
theonion.com/how-hurrican...
theonion.com/how-hurrican...
Reposted by Dan Dawson
An atmospheric general circulation model you can run on a Python Jupyter notebook?! Heck yeah! Check out this project- both an educational tool for undergraduates/graduate students, and a research tool for scientists interested in idealized climate modeling.
journals.ametsoc.org/view/journal...
journals.ametsoc.org/view/journal...
journals.ametsoc.org
October 13, 2025 at 7:35 PM
An atmospheric general circulation model you can run on a Python Jupyter notebook?! Heck yeah! Check out this project- both an educational tool for undergraduates/graduate students, and a research tool for scientists interested in idealized climate modeling.
journals.ametsoc.org/view/journal...
journals.ametsoc.org/view/journal...
I see Frame-Pritchard Alley is heating up again!
October 3, 2025 at 8:08 PM
I see Frame-Pritchard Alley is heating up again!
Very important point here! A raw ensemble mean can sometimes be very misleading!
IMPORTANT NOTE 🚨
When looking at ensemble means, beware of the "survivors bias". For example, the GEFS *mean* misses the coast... but most GEFS members make landfall!
This has to do with the storm timing. Consider how some members move the storm faster than others... (cont.)
When looking at ensemble means, beware of the "survivors bias". For example, the GEFS *mean* misses the coast... but most GEFS members make landfall!
This has to do with the storm timing. Consider how some members move the storm faster than others... (cont.)
September 26, 2025 at 2:37 PM
Very important point here! A raw ensemble mean can sometimes be very misleading!
Reposted by Dan Dawson
I am so excited to announce that one of the radar meteorology courses that I developed with @comet-meted.bsky.social is now available! "Dual-Polarization Fundamentals" picks up where "Weather Radar Fundamentals" left off! learn.meted.ucar.edu#/online-cour... (Register on learn.meted.ucar.edu first.)
September 14, 2025 at 5:21 PM
I am so excited to announce that one of the radar meteorology courses that I developed with @comet-meted.bsky.social is now available! "Dual-Polarization Fundamentals" picks up where "Weather Radar Fundamentals" left off! learn.meted.ucar.edu#/online-cour... (Register on learn.meted.ucar.edu first.)
Reposted by Dan Dawson
The online ghouls who are celebrating and/or justifying the shooting of Charlie Kirk have no idea how much damage they are doing…
September 10, 2025 at 8:39 PM
The online ghouls who are celebrating and/or justifying the shooting of Charlie Kirk have no idea how much damage they are doing…
Apropos of nothing, I offer an unsolicited academic writing tip. Sentences that begin with some form of "Fig. X shows so-and-so..." are usually unnecessary, as they often just regurgitate what should be in the figure caption. Instead, *interpret* the figures in the text with appropriate references.
September 9, 2025 at 2:04 AM
Apropos of nothing, I offer an unsolicited academic writing tip. Sentences that begin with some form of "Fig. X shows so-and-so..." are usually unnecessary, as they often just regurgitate what should be in the figure caption. Instead, *interpret* the figures in the text with appropriate references.
Ep 32 of ongoing #Kilauea eruption is in full fountaining mode, and as of the time of this post, there is an amazing, quasi-steady intense "lavanado" ongoing in the shear zone next to the angled lava fountain. Ready-made source of horizontal shear and stretching!
www.youtube.com/live/BqmpkUd...
www.youtube.com/live/BqmpkUd...
[V3cam] Kīlauea volcano, Hawaii (south Halemaʻumaʻu crater)
YouTube video by USGS
www.youtube.com
September 2, 2025 at 5:19 PM
Ep 32 of ongoing #Kilauea eruption is in full fountaining mode, and as of the time of this post, there is an amazing, quasi-steady intense "lavanado" ongoing in the shear zone next to the angled lava fountain. Ready-made source of horizontal shear and stretching!
www.youtube.com/live/BqmpkUd...
www.youtube.com/live/BqmpkUd...
Hey, I know this guy!
This week’s #Phoenix storms were a reminder: powerful winds drive dust storms, wildfires and even blizzards.
A weather scientist explains the pressure changes that unleash them:
A weather scientist explains the pressure changes that unleash them:
What causes the powerful winds that fuel dust storms, wildfires and blizzards? A weather scientist explains
One long line of powerful winds can whip up dust storms, spread wildfires, spin up tornadoes and fuel blizzards – all at the same time across different states.
buff.ly
August 26, 2025 at 10:16 PM
Hey, I know this guy!
Reposted by Dan Dawson
Robot meets bollard. Nothing beats the #WorldBollardAssociation
August 23, 2025 at 10:55 AM
Robot meets bollard. Nothing beats the #WorldBollardAssociation